linux/drivers/staging/octeon-usb
Christoph Hellwig 7b81cb6bdd usb: add a HCD_DMA flag instead of guestimating DMA capabilities
The usb core is the only major place in the kernel that checks for
a non-NULL device dma_mask to see if a device is DMA capable.  This
is generally a bad idea, as all major busses always set up a DMA mask,
even if the device is not DMA capable - in fact bus layers like PCI
can't even know if a device is DMA capable at enumeration time.  This
leads to lots of workaround in HCD drivers, and also prevented us from
setting up a DMA mask for platform devices by default last time we
tried.

Replace this guess with an explicit HCD_DMA that is set by drivers that
appear to have DMA support.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190816062435.881-4-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-21 10:03:35 -07:00
..
Kconfig staging: add missing SPDX lines to Kconfig files 2019-04-03 11:10:15 +02:00
Makefile Staging: octeon-usb: Adding SPDX license identifier 2018-07-27 17:18:14 +02:00
octeon-hcd.c usb: add a HCD_DMA flag instead of guestimating DMA capabilities 2019-08-21 10:03:35 -07:00
octeon-hcd.h staging: octeon-usb octeon-hcd: Fix several typos. 2019-03-18 07:06:08 +01:00
TODO staging: octeon-usb: update TODO 2016-02-25 22:38:16 -08:00